Steve, regarding the throttle servo--what size is the tank? The C/L FAI flight is a maximum of 8 minutes IIRC, and the vast majority is at less than full throttle. My twin takes less than 5 minutes which includes a flap demo that takes about 7 or 8 laps. It is hard to tell but you might be able to get by with a smaller tank and mount the servo(s) beside it.
Chuck